GRAUPNER 32032, Руководство по программированию

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190 Detail program description - Helicopter mixer / Auto-rotation settings
Helicopter mixers
Auto-rotation setting
Auto-rotation permits both full-size and model
helicopters to land safely in a crisis, e. g. if the motor
should fail. Moreover, if the tail rotor should fail,
cutting the motor and landing using auto-rotation is
also the only possible way to avoid a high-speed,
uncontrollable rotation around the vertical axis
and a resulting catastrophic crash – which is why a
switchover TO the auto-rotation phase takes place
immediately.
When the switchover to the auto-rotation phase is
made, the Helicopter mixer menu screen changes as
follows:
Pitch
–90%
Tail rot. offset AR 0%
Thr. position AR
Gyro suppression
Swashplate rotation
Swashplate limiter
0%
0°
AUS
Œ
Gyro offset 0%
Autorot
During auto-rotation fl ight, the main rotor is no longer
driven by the motor but only by its own momentum and
the the airfl ow through the rotor plane during descent.
Since the energy stored by a rotor kept spinning in this
way is rapidly consumed if the helicopter fl ares, pilots
must not only have experience in handling helicopter
models but must also consider carefully how the
relevant functions should be confi gured.
The advanced pilot should therefore practice auto-
rotation landings at regular intervals. Not only to be
able to demonstrate mastery of the maneuver at
competitions, but also to ensure the pilot can can
land the helicopter undamaged from a great height if
the motor should fail. For this purpose, the program
provides a range of adjustment options designed to
help the pilot fl y a motorized model in its unpowered
state. Note that the auto-rotation settings comprise a
complete seventh fl ight phase, which provides access
to all the fl ight phase- specifi c confi guration options,
and to trims, collective pitch curve settings, etc.,
in particular. The following functions have special
features not present in the powered fl ight phases:
Pitch (Collective pitch curve (C1
¼
Pitch))
In powered fl ight, the maximum blade pitch angle is
limited by available motor power. In auto-rotation,
however, it is limited only by the point at which airfl ow
ceases over the main rotor blades. Greater maximum
collective pitch must therefore be set to ensure
suffi cient thrust when fl aring the helicopter even as
rotational speed is falling off. To do so, briefl y tap
the center
SET key of the right touch pad to switch
to the "Pitch" graph page and then use the joystick
to move the vertical line to point "H". Start by setting
a value that is about 10 to 20 %
greater than your
"normal" maximum value for collective pitch. Initially,
however, do NOT set a value that is considerably
greater than for normal fl ight, since, if this is done,
the behavior of the collective pitch controls may then
be very unfamiliar following the switchover. Indeed,
there is a danger that the pilot will oversteer during
the fl are and the model will balloon: this will case the
rotor speed to collapse at a considerable altitude and
the model will then crash to the ground. The value
can always be readjusted later after fl ying some test
auto-rotations.
The minimum value for collective pitch can differ
from that set for normal fl ight. This depends on the
pilot's usual style for normal fl ight. For auto-rotation,
however, always set a suffi ciently generous minimum
value for collective pitch at point "L" to ensure
the model can be brought out of forward fl ight at
moderate speed into a descent at an angle of around
60 … 70 degrees when collective pitch is reduced to
a minimum. If, like most helicopter pilots, you have
used this kind of setting for normal fl ight anyway, then
this value can simply be transferred.
If, however, you normally let your model "fall" at a
shallower angle, then you should increase the value
at point "L", and vice versa.
Approach angle for
various wind conditions
Approach angle
in moderate
wind
no wind
45°
60°
75°
in strong
wind
As a rule, the collective pitch stick itself is not
positioned right at the bottom of its travel for auto-
rotation. Instead, it is typically between the hover
position and the bottom end-point. This offers the
pilot an option for further adjustment, e. g. via pitch
inclination through pitch-axis controls.
The approach can be shortened by pulling back
slightly on the pitch-axis joystick and gently reducing
pitch or by extending the approach by pushing
forward on the pitch-axis joystick and carefully
increasing pitch.
Throttle setting AR
Although pilots will be expected to cut the glow
motor completely during competitions, This is rather
inconvenient during training sessions because the
motor must be restarted after every practice auto-
rotation landing.
Therefore, for training sessions, set this line's value
such that a combustion motor is held at a safe idle
without the clutch engaging during the auto-rotation
phase; electric drive systems should be set safely to
"Off".
Note:
The "Motor Stop" option in the »
Base setup model «
menu offers an alternative "Emergency STOP"